US8900312B2

Expandable interbody fusion device with graft chambers

Summary by NHIP

Expandable fusion device with graft channel

The device comprises two endplates and sequentially inserted expansion members that expand between vertebral bodies. A rear channel in the inferior endplate communicates with U-shaped member openings to receive bone graft material.

Claim Score by NHIP

Read claim 1, the broadest

Abstract

An expandable interbody fusion device includes superior and inferior endplates that are configured to receive a sequentially inserted stack of expansion members or wafers in interlocking engagement. The expansion members are formed to each have a generally U-shaped rearward facing opening. The superior and inferior endplates have openings through their outer surfaces in at least partial alignment and communication with the rearward facing openings of the expansion members. The inferior endplate has a fully bounded cavity for telescoping receipt of the superior endplate. The inferior endplate also has a fully bounded channel extending through the rear endwall thereof in direct communication with the rearward facing opening of at least one expansion member for the receipt of bone graft material into the device to promote fusion between opposing vertebral bodies of the spine.

US8900312B2, drawing sheet 1
Sheet 1 of 12

Term

Projected expiry 19 May 2033.

  1. Priority and filed
  2. Granted
  3. Today
  4. Projected expiry

30 claims: 3 independent, 27 dependent

  1. 1
    Broadest claimClaim Score 32, narrow(NHIP)An expandable interbody fusion device for implantation into an intradiscal space between two opposing vertebral bodies of a spine, comprising:a first endplate having an outer surface configured to contact one of said vertebral bodies and an opening extending through said outer surface;a second endplate having an outer surface configured to contact the other vertebral body and an inner support surface, said second endplate having opposing spaced apart sidewalls and opposing spaced apart front and rear endwalls defining therewithin a fully bounded interior cavity, said support surface being within said interior cavity, said first endplate being received within said interior cavity, said second endplate having at least one opening extending through said outer surface and said support surface and communicating with said interior cavity, said rear endwall defining therethrough a fully bounded channel in communication with said interior cavity, said first endplate being movable in an expansion direction relative to said second endplate toward the opposing vertebral body;at least one elongate expansion member having a front end and a rear end configured to be introduced through said channel into said interior cavity in an insertion direction that is substantially perpendicular to said expansion direction and supported by said support surface therewithin with the front end of said expansion member adjacent the front endwall of said second endplate and the rear end of said expansion member adjacent the rear endwall of said second endplate, said expansion member having an open rearward facing opening extending through the rearmost surface of said rear end and communicating with said channel and in at least partial alignment with said openings through said first endplate and said second endplate;and cooperating locking surfaces on said expansion member and one of said first endplate and said second endplate member to lock said expansion member in said device.
  2. 17
    An expandable interbody fusion device for implantation into an intradiscal space between two opposing vertebral bodies of a spine, comprising:a first endplate having an outer surface configured to contact one of said vertebral bodies and an opening extending through said outer surface and said lower surface;a second endplate having an outer surface configured to contact the other vertebral body and an inner support surface, said second endplate having opposing spaced apart sidewalls and opposing spaced apart front and rear endwalls defining therewithin an interior cavity, said support surface being within said interior cavity, said first endplate being received within said interior cavity, said second endplate having at least one opening extending through said outer surface and said support surface and communicating with said interior cavity, said rear endwall defining therethrough a channel in communication with said interior cavity, said second endplate being movable in an expansion direction relative to said first endplate toward the opposing vertebral body;a plurality of elongate expansion members each having a front end and a rear end and configured to be introduced through said channel into said interior cavity one below the other in an insertion direction that is substantially perpendicular to said expansion direction and supported by said support surface therewithin with the front end of each of said expansion members adjacent the front endwall of said second endplate and the rear end of each of said expansion members adjacent the rear endwall of said second endplate, each of said expansion members having an open rearward facing opening extending through the rearmost surface of said rear end and communicating with each other upon introduction and in at least partial alignment with said openings through said first endplate and said second endplate, the rearward facing opening of at least said lowermost expansion member being in direct communication with said channel.
  3. 23
    An expandable interbody fusion device for implantation into an intradiscal space between two opposing vertebral bodies of a spine, comprising:a first endplate having an outer surface configured to contact one of said vertebral bodies and an opening extending through said outer surface;a second endplate having an outer surface configured to contact the other vertebral body and an inner support surface, said second endplate having opposing spaced apart sidewalls and opposing spaced apart front and rear endwalls defining therewithin a fully bounded interior cavity, said support surface being within said interior cavity, said first endplate being received within said interior cavity, said second endplate having at least one opening extending through said outer surface and said support surface and communicating with said interior cavity, said rear endwall defining therethrough a fully bounded channel in communication with said interior cavity, said first endplate being movable in an expansion direction relative to said second endplate toward the opposing vertebral body;at least one insert having an upper surface, an opposite lower surface, a front end, a rear end and an open rearward facing opening extending through said upper surface, said lower surface and the rearmost surface of said rear end, said at least one insert being configured to be introduced between said first endplate and said second endplate through said channel into said interior cavity in an insertion direction that is substantially perpendicular to said expansion direction and supported by said support surface therewithin with the front end of said insert adjacent the front endwall of said second endplate and the rear end of said insert adjacent the rear endwall of said second endplate, said rearward facing opening communicating with said channel and being in at least partial alignment with said openings through said first endplate and said second endplate;and cooperating locking surfaces on said at least one insert and one of said first endplate and said second endplate member to lock said at least one insert in said device.